• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.301-306
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• 2001

Applying life cycle assessment in PCB (printed circuit board) production, most of environmental impacts come from outside-factory-process due to power generation, especially, and other raw material productions. Relatively, small environmental impacts of inside-factory-process make it difficult to compare them. To overcome this problem allocating environmental impacts of outside-factory-process on inside-factory-process. It helps to identify the environmental impacts of each process and find sources of environmental impacts. Also, life cycle assessment shows reduction of environmental impacts after copper recycling process.

• 대한약리학회지
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• 제25권1호
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• pp.93-99
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• 1989

본 교실의 연구결과에 의하면 토끼와 흰쥐에서 수정란 착상시기에 peripheral lymphocyte와 thymocyte의 활성도가 저하될 뿐만 아니라 착상기간중 생성되는 prostaglandin E(PGE)의 생리적인 농도로도 peripheral lymphocyte와 thymocyte의 활성도가 억제되었다. 그러므로 본 연구에서는 흰쥐의 착상시기에 전신적인 면역기능 뿐만 아니라 국소적으로 DLN lymphocyte의 활성도가 억제되는지를 관찰하고 PGE가 어떠한 기전으로 모체의 면역기능을 억제하는가를 관찰하여 다음과 같은 결과를 얻었다. 1. 흰쥐의 착상시기에 DLN lymphocyte의 활성도가 임신하기 않은 흰쥐의 DLN lymphocyte에 비하여 통계적으로 유의하지는 않으나 저하되었으며 이러한 저하현상은 100% 흰쥐에서 관찰되었다. 2. 착상시기의 DLN lymphocyte에 prostaglandin 합성억제제인 indomethacin(ID)를 처리하면 DLN lymphocyte의 활성도가 통계적으로 유의하게 증가하였다. 그러나 임신하지 않은 흰쥐의 DLN lymphocyte의 활성도는 증가되어 있으나 $PGE_2$를 전처리하면 DLN lymphocyte의 활성도가 유의하게 억제되며 $PGE_2$를 전처치한 후 ID를 처리하면 DLN lymphocyte의 활성도가 $PGE_2$로 전처치하지 않고 ID를 처리한 경우에 비하여 유의하게 증가하였다. 그러나 $PGE_2$ 대신estradiol, progesterone 및 hCG를 전처치하였을 경우에는 ID 처리로 DLN lymphocyte의 활성도가 증가하지 않았다. 3. 임신하지 많은 흰쥐의 DLN lymphocyte에 $PGE_2$를 전처리하면 PGE-producing cell이 유도되어 PGE 생성이 증가하는지를 확인하기 위하여 $PGE_2$를 전처리하고 Con A를 처리한 후 배양액의 PGE를 정량한 결과 PGE를 전처리하지 않은 DLN lymphocyte에 비하여 유의하게 PGE 생성이 증가하였다. 이상의 결과로 보아 흰쥐의 착상시기에는 모체의 DLN lymphocyte의 활성도가 저하되며, 특히 PCE는 PGE-producing cell을 유도함으로써 착상시기의 모체의 면역기능에 영향을 주는 것으로 생각된다.

• 소성∙가공
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• 제19권2호
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• pp.132-137
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• 2010

In the multi-pass shape drawing process, the appropriate process design is very important to produce sound products. The reduction ratio, die angle, and the intermediate die shape are very important process variable of the multi-pass shape drawing. The aim of this study is the determination of the reduction ratio, die angle, and the intermediate die shape of the 2 pass shape drawing process for producing steering spline shaft. In this study, FE analysis, Taguchi method, and ANN(artificial neural network) were applied to determine the appropriate reduction ratio, die angle, and intermediate die shape. After the determination of the process variables, FE analysis and drawing experiment were performed to evaluate the effectiveness of the determined process variables. The dimensional accuracy of the final drawn spline shaft was evaluated by using 3D surface profiler and 3D laser digitizing system.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 추계학술대회 논문집
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• pp.139-143
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• 2001

In manufacturing process of semiconductor package, thermal stress owing to high temperature in moulding and bubbles generated in chip bonding process become main causes to producing void. Therefore, on this study we evaluated quantitatively void size by ultrasonic spectroscopy method which analyze the frequency of this received pulse using pulses with broad band frequency, and after destructive test we verified effectiveness of sizing void by ultrasonic spectroscopy as we find error degree between the real size of void and the sizing void by ultrasonic spectroscopy.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.388-390
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• 2003

Paste micro-injection molding process was applied for fabrication of barrier ribs of PDP in an attempt to reduce processing steps and materials loss during the processing. For the paste, a thermally curable one was used and for the mold, a polymeric soft mold was used. It was demonstrated that the micro-molding process can be used successfully in producing barrier ribs of PDP.

• 기술혁신연구
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• 제9권2호
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• pp.98-119
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• 2001

The purpose of this study is to classify the world countries into several cluste on the basis of the characteristics of the scientific and technological development, and analyse the main factors of development in each cluster. Major contributions of this study can be summarized as follows: (1) In the process of producing the composite indicators, individual indicators were adopted only if they met the condition which were logically compliable for the given time periods. Hence this thesis supports the reliability in comparing results of analysis in each period of years. (2) Could clearly capture the development characteristics and its changing process in each country.

• KSBB Journal
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• 제16권2호
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• pp.107-114
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• 2001

The dynamic evolution process has resulted in the myriad shapes, functions, and systems evident in every living organism. For centuries, people have been harnessing the power of evolution to produce new varieties of plants and animals, such as producing tomatoes from berries and Chihuahuas from wolves. Now scientists are using it to produce better molecules, ranging from drugs to industrial chemicals, and doing it in days or weeks rather than eons. The ingenious process, which creates genetic diversity and selects those with desired features in the laboratory, is called directed evolution or test tube evolution. In this paper, concepts of directed molecular evolution and some examples will be discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.9-10
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• 2005

Process diagrams of selective epitaxial growth of silicon(SEG) could be developed from CVD thermodynamics. They could not only be helpful with understanding of the mechanism, but also offer good processing guidelines in manufacturing high density devices. Through the process optimization skill, applications of SEG to high-density device structures could be possible without problems such as loading effect and facet generation, with producing outstanding electronic properties.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.220.3-220.3
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• 2003

Enantiomers of pindolol were prepared by chromatographic method. Racemic pindolol was derivatized with S-(-)-menthyl chloroformate((-)-MCF) forming its diastereomer, R-(+)-pindolol-(-)-MCF and S-(-)-pindolol-(-)-MCF. The diastereomer mixture was then chromatographically resolved to each diastereomer. Each diastereomer was further hydrolyzed with alkali to each enantiomer quantitatively. Racemization was not occurred in this process. Pindolol enantiomers were recovered producing good yield over 30% over all process.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 13th KACG Technical Meeting `97 Industrial Crystallization Symposium(ICS)-Doosan Resort, Chunchon, October 30-31, 1997
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• pp.33-38
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• 1997

Fundamentals and industrial applications of crystallization of organic compounds are reviewed. The methods to upgrade organic products in terms of its purity and its morphology are introduced. How crystallization of organics can be useful in producing ultra-pure materials are also described.